This is a medium model that is identical to Buildings.Media.GasesPTDecoupled.MoistAir, except that the water vapor is not condensing to the liquid phase if Xi[Water] > X_sat. Instead, all water is assumed in vapor phase.
This new formulation often leads to smaller systems of nonlinear equations because it allows to invert the function T_phX analytically.
Extends from Modelica.Media.Interfaces.PartialCondensingGases (Base class for mixtures of condensing and non-condensing gases).
Name | Description |
---|---|
Water=1 | Index of water (in substanceNames, massFractions X, etc.) |
Air=2 | Index of air (in substanceNames, massFractions X, etc.) |
k_mair=steam.MM/dryair.MM | ratio of molar weights |
dryair=Buildings.Media.PerfectGases.Common.SingleGasData.Air | |
steam=Buildings.Media.PerfectGases.Common.SingleGasData.H2O | |
BaseProperties | |
Xsaturation | Steam water mass fraction of saturation boundary in kg_water/kg_moistair |
setState_pTX | Thermodynamic state as function of p, T and composition X |
setState_phX | Thermodynamic state as function of p, h and composition X |
setState_dTX | Thermodynamic state as function of d, T and composition X |
gasConstant | Gas constant (computation neglects liquid fraction) |
saturationPressureLiquid | Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned |
sublimationPressureIce | Saturation curve valid for 223.16 <= T <= 273.16. Outside of these limits a (less accurate) result is returned |
saturationPressure | Saturation curve valid for 223.16 <= T <= 373.16 (and slightly outside with less accuracy) |
pressure | Gas pressure |
temperature | Gas temperature |
density | Gas density |
specificEntropy | Specific entropy (liquid part neglected, mixing entropy included) |
enthalpyOfVaporization | Enthalpy of vaporization of water |
HeatCapacityOfWater | Specific heat capacity of water (liquid only) which is constant |
enthalpyOfLiquid | Enthalpy of liquid (per unit mass of liquid) which is linear in the temperature |
der_enthalpyOfLiquid | Temperature derivative of enthalpy of liquid per unit mass of liquid |
enthalpyOfCondensingGas | Enthalpy of steam per unit mass of steam |
der_enthalpyOfCondensingGas | Derivative of enthalpy of steam per unit mass of steam |
enthalpyOfGas | Enthalpy of gas mixture per unit mass of gas mixture |
enthalpyOfDryAir | Enthalpy of dry air per unit mass of dry air |
der_enthalpyOfDryAir | Derivative of enthalpy of dry air per unit mass of dry air |
specificHeatCapacityCp | Specific heat capacity of gas mixture at constant pressure |
specificHeatCapacityCv | Specific heat capacity of gas mixture at constant volume |
dynamicViscosity | dynamic viscosity of dry air |
thermalConductivity | Thermal conductivity of dry air as a polynomial in the temperature |
specificEnthalpy | Specific enthalpy |
specificInternalEnergy | Specific internal energy |
specificGibbsEnergy | Specific Gibbs energy |
specificHelmholtzEnergy | Specific Helmholtz energy |
h_pTX | Compute specific enthalpy from pressure, temperature and mass fraction |
T_phX | Compute temperature from specific enthalpy and mass fraction |
Inherited | |
ThermodynamicState | thermodynamic state variables |
FluidConstants | extended fluid constants |
fluidConstants | constant data for the fluid |
moleToMassFractions | Return mass fractions X from mole fractions |
massToMoleFractions | Return mole fractions from mass fractions X |
mediumName="unusablePartialMedium" | Name of the medium |
substanceNames={mediumName} | Names of the mixture substances. Set substanceNames={mediumName} if only one substance. |
extraPropertiesNames=fill("", 0) | Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused |
singleState | = true, if u and d are not a function of pressure |
reducedX=true | = true if medium contains the equation sum(X) = 1.0; set reducedX=true if only one substance (see docu for details) |
fixedX=false | = true if medium contains the equation X = reference_X |
reference_p=101325 | Reference pressure of Medium: default 1 atmosphere |
reference_T=298.15 | Reference temperature of Medium: default 25 deg Celsius |
reference_X=fill(1/nX, nX) | Default mass fractions of medium |
p_default=101325 | Default value for pressure of medium (for initialization) |
T_default=Modelica.SIunits.Conversions.from_degC(20) | Default value for temperature of medium (for initialization) |
h_default=specificEnthalpy_pTX(p_default, T_default, X_default) | Default value for specific enthalpy of medium (for initialization) |
X_default=reference_X | Default value for mass fractions of medium (for initialization) |
nS=size(substanceNames, 1) | Number of substances |
nX=nS | Number of mass fractions |
nXi=if fixedX then 0 else if reducedX then nS - 1 else nS | Number of structurally independent mass fractions (see docu for details) |
nC=size(extraPropertiesNames, 1) | Number of extra (outside of standard mass-balance) transported properties |
setState_psX | Return thermodynamic state as function of p, s and composition X or Xi |
prandtlNumber | Return the Prandtl number |
heatCapacity_cp | alias for deprecated name |
heatCapacity_cv | alias for deprecated name |
isentropicExponent | Return isentropic exponent |
isentropicEnthalpy | Return isentropic enthalpy |
velocityOfSound | Return velocity of sound |
isobaricExpansionCoefficient | Return overall the isobaric expansion coefficient beta |
beta | alias for isobaricExpansionCoefficient for user convenience |
isothermalCompressibility | Return overall the isothermal compressibility factor |
kappa | alias of isothermalCompressibility for user convenience |
density_derp_h | Return density derivative wrt pressure at const specific enthalpy |
density_derh_p | Return density derivative wrt specific enthalpy at constant pressure |
density_derp_T | Return density derivative wrt pressure at const temperature |
density_derT_p | Return density derivative wrt temperature at constant pressure |
density_derX | Return density derivative wrt mass fraction |
molarMass | Return the molar mass of the medium |
specificEnthalpy_pTX | Return specific enthalpy from p, T, and X or Xi |
density_pTX | Return density from p, T, and X or Xi |
temperature_phX | Return temperature from p, h, and X or Xi |
density_phX | Return density from p, h, and X or Xi |
temperature_psX | Return temperature from p,s, and X or Xi |
density_psX | Return density from p, s, and X or Xi |
specificEnthalpy_psX | Return specific enthalpy from p, s, and X or Xi |
AbsolutePressure | Type for absolute pressure with medium specific attributes |
Density | Type for density with medium specific attributes |
DynamicViscosity | Type for dynamic viscosity with medium specific attributes |
EnthalpyFlowRate | Type for enthalpy flow rate with medium specific attributes |
MassFlowRate | Type for mass flow rate with medium specific attributes |
MassFraction | Type for mass fraction with medium specific attributes |
MoleFraction | Type for mole fraction with medium specific attributes |
MolarMass | Type for molar mass with medium specific attributes |
MolarVolume | Type for molar volume with medium specific attributes |
IsentropicExponent | Type for isentropic exponent with medium specific attributes |
SpecificEnergy | Type for specific energy with medium specific attributes |
SpecificInternalEnergy | Type for specific internal energy with medium specific attributes |
SpecificEnthalpy | Type for specific enthalpy with medium specific attributes |
SpecificEntropy | Type for specific entropy with medium specific attributes |
SpecificHeatCapacity | Type for specific heat capacity with medium specific attributes |
SurfaceTension | Type for surface tension with medium specific attributes |
Temperature | Type for temperature with medium specific attributes |
ThermalConductivity | Type for thermal conductivity with medium specific attributes |
PrandtlNumber | Type for Prandtl number with medium specific attributes |
VelocityOfSound | Type for velocity of sound with medium specific attributes |
ExtraProperty | Type for unspecified, mass-specific property transported by flow |
CumulativeExtraProperty | Type for conserved integral of unspecified, mass specific property |
ExtraPropertyFlowRate | Type for flow rate of unspecified, mass-specific property |
IsobaricExpansionCoefficient | Type for isobaric expansion coefficient with medium specific attributes |
DipoleMoment | Type for dipole moment with medium specific attributes |
DerDensityByPressure | Type for partial derivative of density with resect to pressure with medium specific attributes |
DerDensityByEnthalpy | Type for partial derivative of density with resect to enthalpy with medium specific attributes |
DerEnthalpyByPressure | Type for partial derivative of enthalpy with resect to pressure with medium specific attributes |
DerDensityByTemperature | Type for partial derivative of density with resect to temperature with medium specific attributes |
Choices | Types, constants to define menu choices |
constant Integer Water=1 "Index of water (in substanceNames, massFractions X, etc.)";
constant Integer Air=2 "Index of air (in substanceNames, massFractions X, etc.)";
constant Real k_mair = steam.MM/dryair.MM "ratio of molar weights";
constant Buildings.Media.PerfectGases.Common.DataRecord dryair= Buildings.Media.PerfectGases.Common.SingleGasData.Air;
constant Buildings.Media.PerfectGases.Common.DataRecord steam= Buildings.Media.PerfectGases.Common.SingleGasData.H2O;
Type | Name | Default | Description |
---|---|---|---|
Boolean | standardOrderComponents | true | if true, and reducedX = true, the last element of X will be computed from the other ones |
Advanced | |||
Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
redeclare replaceable model extends BaseProperties( T(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default), p(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default), Xi(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)) /* p, T, X = X[Water] are used as preferred states, since only then all other quantities can be computed in a recursive sequence. If other variables are selected as states, static state selection is no longer possible and non-linear algebraic equations occur. */ MassFraction x_water "Mass of total water/mass of dry air"; Real phi "Relative humidity"; protected constant SI.MolarMass[2] MMX = {steam.MM,dryair.MM} "Molar masses of components"; // MassFraction X_liquid "Mass fraction of liquid water"; // MassFraction X_steam "Mass fraction of steam water"; MassFraction X_air "Mass fraction of air"; MassFraction X_sat "Steam water mass fraction of saturation boundary in kg_water/kg_moistair"; MassFraction x_sat "Steam water mass content of saturation boundary in kg_water/kg_dryair"; AbsolutePressure p_steam_sat "Partial saturation pressure of steam"; constant AbsolutePressure pStp = 101325 "Pressure for which dStp is defined"; constant Density dStp = 1.2 "Fluid density at pressure pStp"; equation assert(T >= 200.0 and T <= 423.15, " Temperature T is not in the allowed range 200.0 K <= (T =" + String(T) + " K) <= 423.15 K required from medium model \"" + mediumName + "\"."); MM = 1/(Xi[Water]/MMX[Water]+(1.0-Xi[Water])/MMX[Air]); p_steam_sat = min(saturationPressure(T),0.999*p); X_sat = min(p_steam_sat * k_mair/max(100*Modelica.Constants.eps, p - p_steam_sat)*(1 - Xi[Water]), 1.0) "Water content at saturation with respect to actual water content"; // X_liquid = max(Xi[Water] - X_sat, 0.0); // X_steam = Xi[Water]-X_liquid; X_air = 1-Xi[Water]; h = specificEnthalpy_pTX(p,T,Xi); R = dryair.R*(1 - Xi[Water]) + steam.R*Xi[Water]; // u = h - R*T; // d = p/(R*T); d/dStp = p/pStp; /* Note, u and d are computed under the assumption that the volume of the liquid water is neglible with respect to the volume of air and of steam */ state.p = p; state.T = T; state.X = X; // this x_steam is water load / dry air!!!!!!!!!!! x_sat = k_mair*p_steam_sat/max(100*Modelica.Constants.eps,p - p_steam_sat); x_water = Xi[Water]/max(X_air,100*Modelica.Constants.eps); phi = p/p_steam_sat*Xi[Water]/(Xi[Water] + k_mair*X_air); end BaseProperties;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
MassFraction | X_sat | Steam mass fraction of sat. boundary [kg/kg] |
function Xsaturation = Buildings.Media.PerfectGases.MoistAir.Xsaturation "Steam water mass fraction of saturation boundary in kg_water/kg_moistair";
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state |
redeclare function setState_pTX "Thermodynamic state as function of p, T and composition X" extends Buildings.Media.PerfectGases.MoistAir.setState_pTX; end setState_pTX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[:] | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |
redeclare function setState_phX "Thermodynamic state as function of p, h and composition X" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[:] "Mass fractions"; output ThermodynamicState state; algorithm state := if size(X,1) == nX then ThermodynamicState(p=p,T=T_phX(p,h,X),X=X) else ThermodynamicState(p=p,T=T_phX(p,h,X), X=cat(1,X,{1-sum(X)})); end setState_phX;
Type | Name | Default | Description |
---|---|---|---|
Density | d | density [kg/m3] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state |
redeclare function setState_dTX "Thermodynamic state as function of d, T and composition X" extends Buildings.Media.PerfectGases.MoistAir.setState_dTX; end setState_dTX;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | R | mixture gas constant [J/(kg.K)] |
redeclare function gasConstant "Gas constant (computation neglects liquid fraction)" extends Buildings.Media.PerfectGases.MoistAir.gasConstant; end gasConstant;
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | saturation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | saturation pressure [Pa] |
function saturationPressureLiquid = Buildings.Media.PerfectGases.MoistAir.saturationPressureLiquid "Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned";
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | sublimation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | sublimation pressure [Pa] |
function sublimationPressureIce = Buildings.Media.PerfectGases.MoistAir.sublimationPressureIce "Saturation curve valid for 223.16 <= T <= 273.16. Outside of these limits a (less accurate) result is returned";
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | saturation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | saturation pressure [Pa] |
redeclare function extends saturationPressure "Saturation curve valid for 223.16 <= T <= 373.16 (and slightly outside with less accuracy)" algorithm psat := Buildings.Utilities.Math.spliceFunction(saturationPressureLiquid(Tsat),sublimationPressureIce(Tsat),Tsat-273.16,1.0); end saturationPressure;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure [Pa] |
redeclare function pressure "Gas pressure" extends Buildings.Media.PerfectGases.MoistAir.pressure; end pressure;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature [K] |
redeclare function temperature "Gas temperature" extends Buildings.Media.PerfectGases.MoistAir.temperature; end temperature;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state |
Type | Name | Description |
---|---|---|
Density | d | Density [kg/m3] |
redeclare function density "Gas density" extends Modelica.Icons.Function; input ThermodynamicState state; output Density d "Density"; algorithm d :=state.p*1.2/101325; end density;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEntropy | s | Specific entropy [J/(kg.K)] |
redeclare function specificEntropy "Specific entropy (liquid part neglected, mixing entropy included)" extends Buildings.Media.PerfectGases.MoistAir.specificEntropy; end specificEntropy;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | r0 | vaporization enthalpy [J/kg] |
redeclare function extends enthalpyOfVaporization "Enthalpy of vaporization of water" algorithm r0 := 2501014.5; end enthalpyOfVaporization;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | [K] |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp_fl | [J/(kg.K)] |
function HeatCapacityOfWater "Specific heat capacity of water (liquid only) which is constant" extends Modelica.Icons.Function; input Temperature T; output SpecificHeatCapacity cp_fl; algorithm cp_fl := 4186; end HeatCapacityOfWater;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | liquid enthalpy [J/kg] |
redeclare replaceable function extends enthalpyOfLiquid "Enthalpy of liquid (per unit mass of liquid) which is linear in the temperature" annotation(derivative=der_enthalpyOfLiquid); algorithm h := (T - 273.15)*4186; end enthalpyOfLiquid;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Temperature | der_T | temperature derivative [K] |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | der_h | derivative of liquid enthalpy [J/(kg.K)] |
replaceable function der_enthalpyOfLiquid "Temperature derivative of enthalpy of liquid per unit mass of liquid" extends Modelica.Icons.Function; input Temperature T "temperature"; input Temperature der_T "temperature derivative"; output SpecificHeatCapacity der_h "derivative of liquid enthalpy"; algorithm der_h := 4186; end der_enthalpyOfLiquid;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | steam enthalpy [J/kg] |
redeclare function enthalpyOfCondensingGas "Enthalpy of steam per unit mass of steam" annotation(derivative=der_enthalpyOfCondensingGas); extends Modelica.Icons.Function; input Temperature T "temperature"; output SpecificEnthalpy h "steam enthalpy"; algorithm h := (T-273.15) * steam.cp + Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.enthalpyOfVaporization(T); end enthalpyOfCondensingGas;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Temperature | der_T | temperature derivative [K] |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | der_h | derivative of steam enthalpy [J/(kg.K)] |
replaceable function der_enthalpyOfCondensingGas "Derivative of enthalpy of steam per unit mass of steam" extends Modelica.Icons.Function; input Temperature T "temperature"; input Temperature der_T "temperature derivative"; output SpecificHeatCapacity der_h "derivative of steam enthalpy"; algorithm der_h := steam.cp; end der_enthalpyOfCondensingGas;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
MassFraction | X[:] | vector of mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | liquid enthalpy [J/kg] |
redeclare replaceable function extends enthalpyOfGas "Enthalpy of gas mixture per unit mass of gas mixture" algorithm h := Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.enthalpyOfCondensingGas(T)*X[Water] + Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.enthalpyOfDryAir(T)*(1.0-X[Water]); end enthalpyOfGas;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | dry air enthalpy [J/kg] |
replaceable function enthalpyOfDryAir "Enthalpy of dry air per unit mass of dry air" annotation(derivative=der_enthalpyOfDryAir); extends Modelica.Icons.Function; input Temperature T "temperature"; output SpecificEnthalpy h "dry air enthalpy"; algorithm h := (T - 273.15)*dryair.cp; end enthalpyOfDryAir;
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Temperature | der_T | temperature derivative [K] |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | der_h | derivative of dry air enthalpy [J/(kg.K)] |
replaceable function der_enthalpyOfDryAir "Derivative of enthalpy of dry air per unit mass of dry air" extends Modelica.Icons.Function; input Temperature T "temperature"; input Temperature der_T "temperature derivative"; output SpecificHeatCapacity der_h "derivative of dry air enthalpy"; algorithm der_h := dryair.cp; end der_enthalpyOfDryAir;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp | Specific heat capacity at constant pressure [J/(kg.K)] |
redeclare replaceable function extends specificHeatCapacityCp "Specific heat capacity of gas mixture at constant pressure" algorithm cp := dryair.cp*(1-state.X[Water]) +steam.cp*state.X[Water]; end specificHeatCapacityCp;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cv | Specific heat capacity at constant volume [J/(kg.K)] |
redeclare replaceable function extends specificHeatCapacityCv "Specific heat capacity of gas mixture at constant volume" algorithm cv:= dryair.cv*(1-state.X[Water]) +steam.cv*state.X[Water]; end specificHeatCapacityCv;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
DynamicViscosity | eta | Dynamic viscosity [Pa.s] |
redeclare function extends dynamicViscosity "dynamic viscosity of dry air" algorithm eta := 1.85E-5; end dynamicViscosity;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
ThermalConductivity | lambda | Thermal conductivity [W/(m.K)] |
redeclare function extends thermalConductivity "Thermal conductivity of dry air as a polynomial in the temperature" import Modelica.Media.Incompressible.TableBased.Polynomials_Temp; algorithm lambda := Polynomials_Temp.evaluate({(-4.8737307422969E-008), 7.67803133753502E-005, 0.0241814385504202}, Modelica.SIunits.Conversions.to_degC(state.T)); end thermalConductivity;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy [J/kg] |
redeclare function extends specificEnthalpy "Specific enthalpy" algorithm h := Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.h_pTX(state.p, state.T, state.X); end specificEnthalpy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | u | Specific internal energy [J/kg] |
redeclare function extends specificInternalEnergy "Specific internal energy" extends Modelica.Icons.Function; algorithm u := Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.h_pTX(state.p,state.T,state.X) - gasConstant(state)*state.T; end specificInternalEnergy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | g | Specific Gibbs energy [J/kg] |
redeclare function extends specificGibbsEnergy "Specific Gibbs energy" extends Modelica.Icons.Function; algorithm g := Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.h_pTX(state.p,state.T,state.X) - state.T*specificEntropy(state); end specificGibbsEnergy;
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | f | Specific Helmholtz energy [J/kg] |
redeclare function extends specificHelmholtzEnergy "Specific Helmholtz energy" extends Modelica.Icons.Function; algorithm f := Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.h_pTX(state.p,state.T,state.X) - gasConstant(state)*state.T - state.T*Buildings.Media.GasesPTDecoupled.MoistAirNoLiquid.specificEntropy(state); end specificHelmholtzEnergy;
Type | Name | Default | Description |
---|---|---|---|
Pressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[nX] | Mass fractions of moist air [1] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy at p, T, X [J/kg] |
function h_pTX "Compute specific enthalpy from pressure, temperature and mass fraction" extends Modelica.Icons.Function; input SI.Pressure p "Pressure"; input SI.Temperature T "Temperature"; input SI.MassFraction X[nX] "Mass fractions of moist air"; output SI.SpecificEnthalpy h "Specific enthalpy at p, T, X"; algorithm h := (T - 273.15)*dryair.cp * (1 - X[Water]) + ((T-273.15) * steam.cp + 2501014.5) * X[Water]; end h_pTX;
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | specific enthalpy [J/kg] | |
MassFraction | X[:] | mass fractions of composition [kg/kg] |
Type | Name | Description |
---|---|---|
Temperature | T | temperature [K] |
function T_phX "Compute temperature from specific enthalpy and mass fraction" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "specific enthalpy"; input MassFraction[:] X "mass fractions of composition"; output Temperature T "temperature"; algorithm T := 273.15 + (h-2501014.5 * X[Water])/(dryair.cp * (1 - X[Water])+steam.cp*X[Water]); end T_phX;